Decause a species that didn't die of old age would very quickly fill up its niche. Reproduction would slow drastically and its rate of evolutionary change would also therefore slow. The non-deathless would outpace and eat it.

I suspect that sleep is more of a bug than a feature. In other words "sleep" was not evolutionarily selected for because there was some advantage to unconscious downtime in itself but instead in evolution's development of brains very advantageous structures were cobbled together but they had the bug that they needed periodic sleep episodes to keep them working. This would suggest that sleep evolved in animals that were inactive at night and it didn't matter if they were unconscious because they didn't have anything else to do at night.

HairBolus:I suspect that sleep is more of a bug than a feature. In other words "sleep" was not evolutionarily selected for because there was some advantage to unconscious downtime in itself but instead in evolution's development of brains very advantageous structures were cobbled together but they had the bug that they needed periodic sleep episodes to keep them working. This would suggest that sleep evolved in animals that were inactive at night and it didn't matter if they were unconscious because they didn't have anything else to do at night.

That's interesting, except that sleep evolved to give neurons time for maintenance. Every animal with a brain undergoes some form of sleep, the length and depth of which is pretty proportionate to the level of brain sophistication.

If it were a big, it would *obviously* be bred out of a species due to competition from predators or non-sleeping members of your own species able to eat & fark while you're 'wasting time'.

Ned Stark:Summoner101: Why did we evolve the ability to grow old and die?

Decause a species that didn't die of old age would very quickly fill up its niche. Reproduction would slow drastically and its rate of evolutionary change would also therefore slow. The non-deathless would outpace and eat it.

HairBolus:I suspect that sleep is more of a bug than a feature. In other words "sleep" was not evolutionarily selected for because there was some advantage to unconscious downtime in itself but instead in evolution's development of brains very advantageous structures were cobbled together but they had the bug that they needed periodic sleep episodes to keep them working. This would suggest that sleep evolved in animals that were inactive at night and it didn't matter if they were unconscious because they didn't have anything else to do at night.

I doubt that very seriously. For one, many animals are nocturnal, so there goes one reason out the window. Being awake means exposing the internal information organization system to the chaotic outer world. The central ganglion needs time to defrag and properly index those inputs. Also, sleep provides a crapton of benefits, and not just neurological. The digestive system does its own, energy-intensive maintenance during low-energy sleep hours.

Why do people always ask why we evolved something? That's not how it works. It evolved because it did - evolution doesn't have intent. The genes survived or they didn't. It's like asking why the planet sustains life... well, if things had happened differently, it wouldn't. It didn't do that on purpose somehow.

Newest research shows that active neurons get "inflamed" while we're awake. They literally swell up as we use them, and the more we use them, the more inflamed they get. They can get so inflamed that the synaptic cleft can become squeezed, making it difficult to "think" with those neurons. Mice that were kept awake, i.e. sleep deprivation, showed highly inflamed neurons.

Sleep allows the neurons to "reset", to reduce swelling. At the same time, they produce heavier doses of neurotransmitters, grow dendrites, become more permeable to neurotransmitters, etc, all to reinforce the neural connections and pathways that were exercised during the day.

It may not be the full answer to "why sleep", however they think that might part of it.

The difference in life cycles between prokaryotes and even single-cell eukaryotes is so vast that even you could comprehend the difference. But I suppose you'd prefer immortality as an E. coli cell to your present existence.

The difference in life cycles between prokaryotes and even single-cell eukaryotes is so vast that even you could comprehend the difference. But I suppose you'd prefer immortality as an E. coli cell to your present existence.

Sort of like you grasp the difference between the Earth's air, gravity, water, pressure, temperature and the deadly emptiness of space?

Quantum Apostrophe:Sort of like you grasp the difference between the Earth's air, gravity, water, pressure, temperature and the deadly emptiness of space?

Funny thing, with my multicellular, eukaryotic brain and hands I can fashion a pressurized steel container to travel through that emptiness in all the comfort and safety of home. Alas, poor E. coli is stuck here on Earth, probably inside a cow intestine, and couldn't even grow eyes to see the stars because eyes are multicellular constructs. But it's immortal, so that makes it all better. Unless the cow craps it out and it dries out and its proteins denature and its cell membrane ruptures. Poor E. coli cell! All alone in the world. Not even fellow specialized organ cells to keep it company. Bye-bye, little prokaryote! We hardly knew ye!

daveinsurgent:Why do people always ask why we evolved something? That's not how it works. It evolved because it did - evolution doesn't have intent. The genes survived or they didn't. It's like asking why the planet sustains life... well, if things had happened differently, it wouldn't. It didn't do that on purpose somehow.

This About That:Summoner101: Why did we evolve the ability to grow old and die?

I'll go with: Because reproduction is accomplished for the most part while young. What happens after that doesn't really matter much to the species, so why waste energy on longevity?

Utilization of a limited resource.

Consider Dallas/Fort Worth in Texas. They had tons of land (It's Texas!), yet when you visit the urban area, you could look around you, close your eyes and have someone drive for 10 minutes down the highway and for a non-local, they would have a very difficult time telling you if the car drove for 10 minutes in a straight line, or doubled back, etc. In addition, the entire area is very much developed in a low density matter. To Dallas/Fort Worth, space was a resource they had in abundance, and there were no pressures to keep development planned or restricted. The result is a city which sprawls without much direction.

Now, consider what people would do if they lived forever (barring misfortune). What incentive would people have to maximize the utilization of an unlimited resource? However, if you limit that resource, even artificially, the uses to which that resource is applied become much more prioritized.

Consider that even now, some people resort to artificial means to remind themselves to maximize their limited resource of life. It's so common, we even have a term for it. The Memento Mori. Such a macabre item which people keep around to remind themselves that they are mortal, and don't have forever to accomplish their goals.

daveinsurgent:Why do people always ask why we evolved something? That's not how it works. It evolved because it did - evolution doesn't have intent. The genes survived or they didn't. It's like asking why the planet sustains life... well, if things had happened differently, it wouldn't. It didn't do that on purpose somehow.

I think you are conflating someone asking the question 'Why did we evolve this' with the question 'Why did this evolve?' (assuming that the first implies an intent to evolve a specific trait) For example, it is perfectly valid to ask, "why did some groups evolve lower levels of melanin pigment?" To say 'it evolved because the genes for that trait survived' isn't a sufficient answer even though it is true. The 'Why' is asking why a specific trait was preserved/eliminated/altered when the selective pressure is not immediately apparent, it's not asking why evolution 'chose' to evolve that trait.

theorellior:The central ganglion needs time to defrag and properly index those inputs. Also, ... The digestive system does its own, energy-intensive maintenance during low-energy sleep hours.

That's a bug not a feature.

natmar_76:Newest research shows that active neurons get "inflamed" while we're awake.

That's a bug not a feature (if true).

If I had designed neurons and brains I would have designed them so that they didn't need any down time. People sometimes compare sleep to garbage collection in programming language systems (such as Lisp, JavaScript, etc.) and surprise surprise such systems can be designed so that garbage collection happens as a background process and there is no need to put the main process to sleep until it is complete.

HairBolus:If I had designed neurons and brains I would have designed them so that they didn't need any down time.

LOL. And if my aunt had balls she'd be my uncle.

HairBolus:People sometimes compare sleep to garbage collection in programming language systems (such as Lisp, JavaScript, etc.) and surprise surprise such systems can be designed so that garbage collection happens as a background process and there is no need to put the main process to sleep until it is complete.

That's nice if you have unlimited cycles at your disposal. Has it ever occurred to you that naturally-selected parsimony in self-replicating organic systems with limited energy resources might actually have found a sleep-wake purging system to be more efficient than constant low-grade garbage collection? Not to mention less taxing on the main ganglion which is already trying to assimilate many different inputs?

Wolf892:Why did we evolve the need to eat meat when other mammals can become just as big and bigger and stronger than us with just a plant based diet?

Because carrion provides more bang for buck in terms of energy than plant matter. This one simple change to our diet allowed our gut to shrink, which helped with the bipedal locomotion thing evolution was having another crack at. It's also considered to be the pivotal point in our history as that crazy high octane fuel went to our head... quite literally.

Yes there are plenty of animals on this planet that are bigger and stronger than us. We're the smartest and thus most dangerous predator on the face of this planet. Not eating sufficient quantities of carrion in their dim and distant past is why you'll find all of these big, strong animals in a zoo and us oggling at them not the other way around.

theorellior:Has it ever occurred to you that naturally-selected parsimony in self-replicating organic systems with limited energy resources might actually have found a sleep-wake purging system to be more efficient than constant low-grade garbage collection? Not to mention less taxing on the main ganglion which is already trying to assimilate many different inputs?

That's a purty explanation full of trying to be incomprehensible big words.

Do you have a purty mouth? And you want to eat me? Otherwise you have have said nothing about sleep being a consequence of bad evolutionary design, i.e. a bug.

daveinsurgent:Why do people always ask why we evolved something? That's not how it works. It evolved because it did - evolution doesn't have intent. The genes survived or they didn't. It's like asking why the planet sustains life... well, if things had happened differently, it wouldn't. It didn't do that on purpose somehow.

Quantum Apostrophe:Ned Stark: Summoner101: Why did we evolve the ability to grow old and die?

Decause a species that didn't die of old age would very quickly fill up its niche. Reproduction would slow drastically and its rate of evolutionary change would also therefore slow. The non-deathless would outpace and eat it.

Count the number of bacteria. Count the number of humans.

Calculate the difference between the earths carrying capacity for viruses and that for humans.

The difference in life cycles between prokaryotes and even single-cell eukaryotes is so vast that even you could comprehend the difference. But I suppose you'd prefer immortality as an E. coli cell to your present existence.

Sort of like you grasp the difference between the Earth's air, gravity, water, pressure, temperature and the deadly emptiness of space?

Good Christ. What the feculant planet of F*ck does this have to do with space? Oh, yes. Nothing.

Ed Grubermann:Quantum Apostrophe: Ned Stark: Summoner101: Why did we evolve the ability to grow old and die?

Decause a species that didn't die of old age would very quickly fill up its niche. Reproduction would slow drastically and its rate of evolutionary change would also therefore slow. The non-deathless would outpace and eat it.

Count the number of bacteria. Count the number of humans.

Calculate the difference between the earths carrying capacity for viruses